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arXiv · 0803.2127

A possible mechanism of ultrafast amorphization in phase-change memory alloys: an ion slingshot from the crystalline to amorphous position

A. V. Kolobov·A. S. Mishchenko·P. Fons·S. M. Yakubenya·J. Tominaga
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Abstract

We propose that the driving force of an ultrafast crystalline-to-amorphous transition in phase-change memory alloys are strained bonds existing in the (metastable) crystalline phase. For the prototypical example of GST, we demonstrate that upon breaking of long Ge-Te bond by photoexcitation Ge ion shot from an octahedral crystalline to a tetrahedral amorphous position by the uncompensated force of strained short bonds. Subsequent lattice relaxation stabilizes the tetrahedral surroundings of the Ge atoms and ensures the long-term stability of the optically induced phase.

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A. V. Kolobov, A. S. Mishchenko, P. Fons, S. M. Yakubenya, J. Tominaga. 2008-03-14. A possible mechanism of ultrafast amorphization in phase-change memory alloys: an ion slingshot from the crystalline to amorphous position. https://doi.org/10.1088/0953-8984/19/45/455209

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